Data storage and retrieval systems are used to store information provided by one or more host computer systems. Such data storage and retrieval systems receive requests to write information to one or more data storage devices, and requests to retrieve information from those one or more data storage devices, where both the requests and the information are communicated over one or more data channels interconnecting the data storage and retrieval system and one or more host computers. Upon receipt of a read request, the system, in certain embodiments, recalls information from the one or more data storage devices and moves that information to a data cache. Thus, the system is continuously moving information to and from one or more host computers, and/or to and from a plurality of data storage devices, and/or to and from one or more data caches.
In addition to reading and writing data, a data storage and retrieval system may receive copy services requests to copy information from a source volume to a target volume. As a general matter, such copy services requests are generated by the one or more host computers, and provided seriatim to the data storage and retrieval system. Generating and providing such copy services requests necessarily requires the one or more host computers to allocate resources to those copy services requests. Receiving, interpreting, and executing such copy services commands necessarily requires the data storage and retrieval system to allocate resources for those copy services requests.
What is needed is an apparatus and method to generate a plurality of commands, such as for example a plurality of copy services requests, external to the one or more host computers, and provide that plurality of commands to the data storage and retrieval system without using one or more data channels.